Skid steer loaders are well knows ground working machines that have hydraulically driven wheels that are fixed for rotation relative to the frame of the machine. Steering is accomplished by controlling the rotation of the wheels on opposite sides of the machine such that a differential in rotational speeds will result in a turning of the machine. The skid steer loader has a centrally positioned operator compartment mounted on the frame with an engine typically located behind the operator. A pair of boom arms is pivotally supported on the frame for vertical movement on opposite sides of the operator compartment. These boom arms are connected together forwardly of the operator compartment with an attachment plate through which various attachments can be mounted to the boom arms.
Skid steer loaders are manufactured in many sizes for use in a variety of operations from cleaning chicken houses to moving materials from one location to another. Because of the versatility of skid steer loaders many attachments have been devised for mounting on the boom arms forwardly of the operator to accomplish the desired operation for the skid steer loader. One simple such attachment is a loader bucket that has a mechanism along the rearward wall to permit connection with the attachment plate and is then operable to scoop materials, such as stone and soil, with the forward movement of the machine and to elevate those materials by vertically moving the boom arms. Hydraulic cylinders controllable by the operator allow the bucket to rotate about a pivot axis to tip the bucket in order for the materials to spill out of the bucket.
Other attachment devices have been created to perform many specialized tasks. One such attachment device is a rock raking apparatus such as is disclosed in U.S. Pat. No. 5,564,506, granted to Phillip Foster, et al on Oct. 15, 1996. This rock raking apparatus includes a loader bucket on which is mounted a pivotally movable rock rake having a toothed rotor that is powered through the hydraulics of the skid steer loader to sweep rocks and other debris into the bucket as the rock rake is moved along the surface of the ground. When the bucket is filled with collected rocks and other debris, the skid steer loader moves to a location for disposal of the debris, whereupon the rock rake is pivoted by hydraulic cylinders away from the front edge of the bucket so that the bucket can be tipped and allow the collected rocks and debris to be emptied from the bucket. The hydraulic cylinders can subsequently be extended to reposition the rock rake in front of the bucket for further operation.
A similar ground-raking and rock gathering attachment device is disclosed in U.S. Pat. No. 4,364,434 granted to Gary Erholm on Dec. 21, 1982. Like the rock raking apparatus of U.S. Pat. No. 5,564,506, this rock gathering attachment has a rock gathering member pivotally mounted to a loader bucket wherein the rock gathering member has a rotatable raking apron that rakes the ground to move rocks and debris rearwardly into the loader bucket. Once filled, the loader is moved to a dump site where the bucket is elevated and then tipped. A connection linkage retains the rock gathering member in a generally horizontal orientation as the bucket is tipped so that the front edge of the bucket and the rock gathering member separate to allow the discharge of the collected debris from the bucket.
Yet another ground raking attachment device is disclosed in U.S. Pat. No. 5,060,732, issued on Oct. 29, 1991, to Theodore Baskett. Similar to the rock raking attachment of U.S. Pat. No. 5,564,506, the loader bucket has a ground raking member pivotally mounted to the bucket so that hydraulic cylinders can rotate the ground raking member away from the front edge of the bucket for discharge of the collected debris from the bucket. This ground raking member also includes a rotatable cylinder formed with a plurality of teeth that rake through the top surface of the ground to collect material rearwardly into the bucket. The rotation of the toothed cylinder is powered by a hydraulic motor carried on the ground raking member and powered from the hydraulic system on the skid steer loader.
A reel-type of rock gathering attachment is disclosed in U.S. Pat. No. 5,682,953, issued to Dale Buysse on Nov. 4, 1997. Similar to the aforementioned rock gathering attachments, the reel is rotatably supported on a pivotally mounted frame that is movable through the extension of hydraulic cylinders to separate the frame from the front edge of the bucket for discharge of collected debris. The bucket of this rock gathering attachment is formed with as a grate along the bottom surface thereof to allow smaller particles of material to fall through the grate while retaining the larger debris within the bucket. Such an apparatus would be particularly adaptable to gathering debris off a sandy beach such that the debris would be retained within the bucket while the sand would be allowed to fall back to the beach.
Soil separators are also known. One such soil separator is disclosed in U.S. Pat. No. 4,839,035, granted on Jun. 13, 1989, to John Iafrate, in which the ungraded soil is loaded into a hopper from which the ungraded soil is discharged into a cylindrical rotor formed with spirally mounted bladed that sweep the ungraded soil against a screen while conveying the unscreened soil to the end of the rotor. Soil passing through the screen is collected and removed from the separating apparatus. The remaining material is discharged from the cylindrical rotor onto a conveyor to be disposed remotely from the separating apparatus.
The soil separating system in U.S. Pat. No. 7,841,422, granted to Joseph Chavez, et al on Nov. 30, 2010, is a mobile apparatus having a front edge that engages the surface of the soil with an elevated conveyor that overrides the sloped floor of the apparatus to move soil, including rocks and other debris, rearwardly toward a collecting bin. The sloped floor includes a stationary screen through which the topsoil particles would pass to return to the ground while the overriding conveyor moves rocks and debris having a size too great to pass through the screen rearwardly into the collection bin.
A push-type compost spreader is shown in U.S. Pat. No. 6,705,552, issued to T. Daniel Ellsaesser on Mar. 16, 2004, in which a small rotor is rotatably supported at the bottom of a hopper to agitate the compost within the hopper to prevent bridging and to break up the compose for discharge through the discharge opening at the bottom of the hopper. The rotor is preferably driven through a ground-drive mechanism, but is formed with axially spaced disks mounted on a rotatable shaft at a canted angle to the axis of the rotor. As a result, the rotation of the rotor provides an undulating action due to the canted mounting of the disks to agitate the compost material funneling down to the bottom of the hopper.
It would be desirable to provide a topsoil spreading attachment device for use with a skid steer loader to enhance the spreading and separating of topsoil being discharge therefrom to the surface of the ground.